Most schools throughout the United States are adopting Schoolwide Positive Behavior Interventions and Supports (SWPBIS). Many school administrators and PBIS teams appear to be implementing SWPBIS without the implementation of a needs assessment to measure preparedness and buy-in prior to a schoolwide initiative. The current research on SWPBIS generally doesn't include lacks information about the needs assessment, the level of need, or the personnel buy-in. The purpose of this study was to measure need and buy-in of a school climate by using a systematic approach implemented within a mixed methods sequential explanatory design (MMSE). The MMSE design used determined the level of need and buy-in towards a SWPBIS model. The MMSE was used in a two phase process: phase one was a survey on school climate and phase two was a series of focus group interviews. The findings demonstrated a high level of need for PBIS but a low level of school personnel buy-in. The findings are presented and implications of the findings are discussed.